Fig 8. A schematic summarizing the role of LCRs in distribution of FG Nups inside the NPC, named “LCR-regulated Coverage”, LCR refers to like charge regions.

Solid lines show a hypothetical initial configuration of FG Nups, while dotted lines show different configurations that FG Nups take over time. FG Nups are categorized into two groups. While one group (including Nsp1, Nup100, and Nup116 shown in (a)) bring their FG domain close to the center of the NPC [24,25] and collectively form a doughnut-like FG network, others (including Nup42, Nup49, Nup57, Nup145N shown in (b)) mostly cover the space next to the wall of the pore. In the first group, LCRs are primarily responsible for the size of the hydrogel formed in the middle (Fig 4), as well as a small opening at the very center of the NPC (Fig 6) [31]. On the other hand, in the second group, LCRs mainly promote interactions of FG Nups in the same layer to cover a larger space inside the pore (Figs 3 and 5).